Local pros · Plumbing and water
Hiring a plumber or water treatment pro
Whole-house filters and softeners go on your main water line, water heaters need venting, drains and often a gas line, and gas ranges and dryers need a gas connection. That's plumbing work, and in most places it's licensed and permitted.
Hire right once: Start with a water test, not a sales pitch. A pro who sizes a softener from your measured hardness and household, and puts the filter ahead of it, sets you up for years without a second system.
Before you hire, check:
- A plumbing license (and gas-fitting license if gas is involved)
- Your water test results: hardness, iron, chlorine or chloramine
- Whether the quote includes the bypass valve, drain, outlet and permit
What they do for these products
- Whole-house filters and softeners: cut into the main line after the shutoff, add a bypass valve, run the softener's drain line with an air gap, and set the regeneration schedule from your hardness and household size.
- Water testing: water treatment specialists test for hardness, iron, manganese, chlorine or chloramine and other contaminants and recommend a system order (sediment, carbon, softener). The Water Quality Association certifies water treatment professionals.[1]
- Water heaters: replace tank, tankless and heat pump water heaters, including venting, expansion tank, relief valve discharge and condensate.
- Gas lines: run or extend gas piping to a range, dryer, grill or standby generator and leak-test it.
Licensing and permits
Most states license plumbers at the state level, and some license gas fitters separately; a few leave licensing to cities or counties. Water heater replacements and new gas piping usually need a permit and inspection. A softener or filter install may or may not need a permit, depending on your plumbing code and whether a new drain connection is involved; ask your installer to confirm locally. If you're on a private well, your county health department may have its own testing guidance.[2]
Questions to ask
- What did my water test show, and how did you size the system from it?
- Which comes first, the filter or the softener, and why?
- Is a bypass valve included, and where will the drain and outlet go?
- Is the system's performance certified to an NSF/ANSI standard for the contaminant I care about?[3]
- Is it a purchase or a rental? If it's a rental, what happens when I sell the house?
- Is the permit included for water heater or gas work?
Typical installed costs
| Job | Typical range |
|---|---|
| Plumber labor | $45–$200 per hour[4] |
| Whole-house water filtration system, installed | $1,500–$10,000[4] |
| Water softener | $700–$3,000[4] |
| Tank water heater, installed | $600–$3,100[5] |
| Tankless water heater, installed | $1,400–$5,600[5] |
| Heat pump water heater, installed | $2,000–$4,600[5] |
| New gas line to an appliance | $250–$750[6] |
Related buying guides
- Whole-house water filters and softeners
- Ranges, ovens and cooktops (gas hookups)
- Washers and dryers (gas dryers)
Sources
- Water Quality Association, Professional Certification: wqa.org
- U.S. EPA, Private Drinking Water Wells: epa.gov
- NSF, Drinking water treatment unit standards: nsf.org
- Angi, Whole-House Water Filtration System Cost: angi.com
- HomeGuide, Water Heater Installation Cost (2026): homeguide.com
- HomeGuide, Gas Line Installation Cost (2026): homeguide.com